1.3.5. DDAM

1. Introduction

      DDAM is an electrochemical analysis method. The target compound is assumed to be an open system to the mobile metals atom A (group I, II, III e.g. Li, Mg or Al). Thus, the corresponding chemical potential μ_A can be represented as a function of the electric potential Φ:μ_A()=μ⁰_A-eqΦ where μ⁰_A is the chemical potential of metallic A, e is the electron charge and q is the number of electrons transferred from A. So, DDAM can be used to determine the decomposition products from oxidation/reduction at a given Φ based on the differences in grand potential, thereby accurately predicting decomposition of some compounds.
   

2. Step-by-Step Guide

   Create a computing task following the steps below

   

   Fig. 1.11 computational_workflow

   
   

   • step 1. Create a new task: Enter the name and description of the computing task on the corresponding page, click the “OK” button to complete the creation of the computing task; click the “Cancel” button to clear the input content

   • step 2. Upload files: Follow the instructions on the corresponding page to upload computing input files.

     Attention:

     • Please make sure to name computing input files in English!

     • If you need to upload multiple computation input files, please compress them into a zip file and upload the zip file.

   • step 3. Set computation parameters: Set computation parameters according to the prompts on the corresponding page.

   • step 4. Set runtime parameters: Currently, no need to set runtime parameters, keep the input box at default settings.

   • step 5. Save computation task: Complete the creation of the computation task and add it to the computation project. On the redirected page, you can choose

     • Continue adding computation tasks: Add a new computation task

     • View Project: View details of the current pending computational project

3. Parameter description

   • Input file

     • stable.json: Contains the chemical formula, internal energy, and band gap of all relevant stable compounds (including pure elements) in the system.

     • The JSON file should be written in the following format:

       {“Chemical Formula 1”: [Energy 1, Energy 2, …], “Chemical Formula 2”: [Energy 1]} {“Li”: [-2.1, -1.9], “Li2S”: [-12.4]}

     • 示例文件

   • Computing Parameters

     Parameters Name	Parameters Type	Description
     Function	——	There are five functions available: plot:Plot the potential-decomposition energy curve windowDE:Compute the decomposition energy of the target compound within the window show_allde_file:Compute the decomposition energy of the target compound at each electric potential show_dpp_file:Compute the electrochemical decomposition process of the target compound dP_and_dC:Compute the oxidation/reduction electric potential of the target compound
     Elements corresponding to atoms are not open in the system	String（String）	Example: Li O
     Chemical formula of the target compound	String（String）	Example: Li2S
     Internal energy of the target compound	Float(Float)
     Chemical formula of the open atomic element	String（String）
     Number of electrons carried by the open atomic element	Positive integer (int)	Default value is 1
     Step size of potential detection	Float(Float)	The default value is 0.1
     Maximum detected potential	Positive integer (int)	The default value is 99
     Initial detection potential	Positive integer (int)	The default value is 0

   • Running Parameters

     Currently no need to set, keep the default settings.

     Parameters Name	Parameters Type	Description
     Machine Name	String（String）	Machine name, default is machine01
     Number of Core	Positive integer (int)	Number of Compute cores, default is 1
     Number of Process	Positive integer (int)	Number of Computing processes, default is 1

4. Computational Result Files

   Different files are generated depending on the Function options

   • plot_data:plot_data.json

   • windowDE:windowDE.json

   • show_dpp_file:show_dpp_file.json

   • show_allde_file:show_allde_file.json

   • dP_and_dC:dP_and_dC.json